Motor driven toy vehicles

ABSTRACT

Motor driven toy vehicles which may assume the form of different vehicle bodies, each having a chassis with a base-plate at the bottom thereof provided with a generally rectangular opening into which may be inserted different and interchangeable module casings containing drive mechanisms for the vehicles. These mechanisms may assume different forms although they are composed essentially of a small direct-current motor, a dry cell for energizing the motor and a switch mechanism for controlling the connections therebetween. One embodiment of module makes possible the movement of the vehicle in forward and backward directions from a position of rest. Another embodiment permits energization of the motor in a single direction only which compels movement of the vehicle in diverse and haphazard directions by combining the steering control for the vehicle with the traction drive therefor.

United States Patent [151 3,659,378 Tong May 2, 1972 [54] MOTOR DRIVEN TOY VEHICLES Primary Examiner-Louis G. Mancene Assistant Examiner-Donald Weinhold, Jr. AttorneySamuel Lebowitz ABSTRACT Motor driven toy vehicles which may assume the form of different vehicle bodies, each having a chassis with a base-plate at the bottom thereof provided with a generally rectangular opening into which may be inserted different and interchangeable module casings containing drive mechanisms for the vehicles. These mechanisms may assume different forms although they are composed essentially of a small direct-current motor, a dry cell for energizing the motor and a switch mechanism for controlling the connections therebetween. One embodiment of module makes possible the movement of the vehicle in forward and backward directions from a position of rest. Another embodiment permits energization of the motor in a single direction only which compels movement of the vehicle in diverse and haphazard directions by combining the steering control for the vehicle with the traction drive therefor.

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sum 5 or 6 ATTORNEY PATENTEHMM 2 I972 SHEET 6 OF 6 R m V m ATTORNEY 1 MOTOR DRIVEN TOY VEHICLES It is the object of the present invention to provide motor driven toy vehicles of rugged construction and low cost which are adapted to be powered by interchangeable modular casings, each of which contains a small electric motor, a dry-cell battery for powering the motor, and a switching device therefor, to control the movement of the vehicle.

It is another object of the invention to provide a plurality of motor vehicles of many different body designs and functions, each having a chassis which is capable of accommodating interchangeable modular power units in accordance with the invention, to attain different modes of operation for the vehicle. Thus, these modular power units may be adapted to control the vehicle for forward and backward operation, in addition to a rest position, or to control the vehicle for movement in random or haphazard directions, in dependence upon the traction characteristics encountered by the vehicle.

It is another object of the invention to provide toy vehicles and modular power units therefor which for the major extent are fabricated from molded plastic compositions and which nevertheless are of extremely rugged design.

Other objects and purposes will appear from the detailed description of the invention following hereinafter, taken in conjunction with the accompanying drawings, wherein FIG. 1 is a front elevation of a toy vehicle in accordance with the invention, with one embodiment of the interchangeable power module casing detached therefrom;

FIG. 2 is a bottom view of the vehicle shown in FIG. 1, with the module in engagement with the vehicle chassis;

FIG. 3 is a front elevation of the lower portion of the vehicle shown in FIG. 1, with portions of the chassis broken away to show the interengagement of the module casing with the baseplate of the chassis;

FIG. 4 is a top view of the module casing in position for engagement with the chassis;

FIG. 5 is an exploded view of module casing in brokendown condition with the separation of its two shell portions, and illustrating the position of the several components of the module;

FIGS. 6,7 and 8 are circuit diagrams of the motor, battery and switching device for controlling 'the movement of the vehicle in a Forward, Ofi and Backward" direction, res ectively; I

FIG. 9 is a perspective' view of the bottom of the vehicle chassis illustrating the mounting of the module casing thereon for detachable interengagement therewith;

FIG. 10 is a right end view of the central portion of FIG. 4, showing the interengagement of the two shell portions constituting the module casing;

FIG. 11 is a vertical sectional view 10;

FIG. 12 is a vertical sectional view along line 12-12 of FIG.

along line 11-11 of FIG.

FIG. 13 is a front end view of a vehicle containing another embodiment of a module casing having different motive capabilities from that shown in FIGS. 1 to 12;

FIG. 14 is a front elevation of the lower portion of a toy vehicle containing the module casing of the second embodiment of the invention, with portions of the chassis broken awa Fl G. 15 is a top view of the module casing shown in FIGS. 13 and 14, with parts broken away to show more clearly the mechanical transmission system of this modified embodiment;

FIG. 16 is a bottom plan view of the unit shown in FIG. 15;

FIG. 17 is a vertical sectional view of the module casing along line 17-17 of FIG. 15;

FIG. 18 is a vertical sectional view along line 18-18 of FIG. 17, with the switching device in position for inactivating the driving motor;

FIG. 19 is a view corresponding to FIG. 18, showing the switch device in position for energizing the motor;

FIG. 20 is a circuit diagram of the module casing shown in no. 17; and

. a position of rest.

FIG. 21 is a perspective view similar to that in FIG. 9, showing the mode of mounti'ng'the modified module casing in the same or similar toy chassis of the toy vehicle.

It is the aim of the invention to provide interchangeable power units for toy vehicles of different designs and operating characteristics such as dump wagons, concrete mixers, sand trucks, etc., which design features do not constitute part of the instant invention.

, FIG. 1 is illustrative of a large number of vehicles V, which may be formed with a suitable cab at the front thereof and a dump wagon D at the rear thereof, which may be moved from the position shown in the drawing to a tilted position around tilting axle A, to simulate a dump truck,'all of which characteristics do not constitute part of the instant invention. Such vehicles may be used as simple pull toys when the module casings are separated therefrom, as indicated in FIG. 1. I

The toy vehicles are mounted on a chassis C which is provided with a base-plate having an elongate opening therein of generally rectangular outline, for the purpose of accommodating within said opening interchangeable power units in the form of module casings M and M which may be readily engaged within any desired vehicle, or disengaged therefrom. These module casings may have diflerent motive characteristics so that the toy vehicle may be operated in different ways, depending upon the specific desire of the child playing with the toy.

Thus, when a module becomes inoperative as a result of the sis of the motor vehicle in order to vary the mode of operation of the toy vehicle.

In the embodiment illustrated in FIGS. 1 to 12 is shown a module casing M capable of driving the vehicle in a forward and reverse direction, in addition to maintaining the vehicle in The universal capability of the toy vehicles in accordance with the invention to accommodate different power units having the same or different characteristics, is made possible by imparting the same external dimensions to the power units for accommodation within an opening 15, in the base-plate 10 of the chassis of generally rectangular outline and of substantially uniform dimensions, in the several toy vehicles. Thus, as shown in FIG. 1, the toy vehicle is generally provided with rear wheels 1,1 mounted on an axle 3 extending between integral lugs projecting from the base plate 10 of the vehicle, and front wheels 2,2 mounted on short axles 4,4 mounted in lugs projecting from the base-plate 10 at the front of the vehicle, as clearly shown in FIGS. 2, 3 and 9. A gear wheel 5 is fixedly mounted on axle 3 for rotation in opposite directions. The opening 15, of generally rectangular outline, is disposed in the base-plate 10 and extends in the direction of the longitudinal axis of the vehicle and is defined by a rear edge 11, front edge 12 and lateral edges 13 and 14.

The module casing M is adapted to be inserted into the belly of the vehicle chassis, as indicated in FIG. 1, and to be supported therein by the engagement of retaining lugs at the rear and front ends of the module with the rear and front edges 11 and 12, respectively, as described in greater detail below.

Furthermore, the positioning of the power module M within the chassis is stabilized by the provision of stop members or lugs 17 projecting laterally from upwardly extending arms 16 at the front of the chassis and by stop members or pins 19 extending downwardly from the upper wall of the chassis, as clearly shown in FIGS. 2 and 3. Preferably these stabilizing lugs and pins are molded integrally with the body of the chas- SIS.

The module casing illustrated inv the first embodiment of the invention is formed of two shell portions 20 and 50 which are interconnected to constitute an integral assembly. FIG. 5 illustrates the disposition of the component parts within the module casing with the top shell 50 removed from the bottom shell but in position to be interengaged therewith by means of lugs at the front and rear ends of the bottom shell with openings in the upper shell 50, which are described in greater the storage battery B. This portion of the upper shell is formed by a bottom 57, front end wall 53 and lateral walls 54,54, the rear ends of which may have nested therein the forward ends of the lateral walls 52,52 which may be heat-sealed therein. The rear portion of the bottom 57 overlies the top of forward shallow portion of the shell 20, and serves to cover the switch mechanism housed in the latter.

The bottom shell 20 is of smaller length thanthe upper shell In order to secure the opposite ends of the axle 43, integral ribs 59 are provided on the inner faces of the lateral walls 52,52 of the upper shell so that the ends thereof press against the ends of the shaft 43 when the upper shell 50 is brought into covering relation with the lower shell 20. It is noted that the portions of the columns 35 for seating the shaft 43 extend beyond the upper edges of the walls 22,22 and the ribs 57 stop short of the bottom edges of the lateral walls of the upper shell, so that the free ends of ribs 59 cover the ends of the shaft 43 while the walls 52,52 confine the ends thereof. Thereby a secure interengagement of the parts results from this arrangeand is constituted by a rear wall 21, lateral walls 22, 22, and

front wall.24. The lateral walls are not of uniform depth and are stepped in order to provide mating edges with the lateral walls of the upper shell portion 50.

The shell 20 is molded with transverse walls 26 and 28 to provide an intermediate compartment 27 for housing a small direct current electric motor E, with cylindrical supports therefor seated in semi-circular recesses in the walls 26 and 28. FIG. 5 shows an annular bearing 41, which may be formed of brass or any other suitable wear-resistant material for, the motor shaft 40, which bearing is seated within the semi-circular recess 32 at the upper portion of the partition wall 28. The opposite end of the motor casing, which may be of Nylon or other wear-resistant material, is supported by a semi-circular saddle in transverse wall 26 so that the motor is supported with stability in the intermediate compartment of the lower shell 20. A transversely extending strap 91, molded on the interior of the upper shell, presses against the top of the motor casing to maintain the motor securely in seated position, with its rotary axis extending longitudinally of the module casing and vehicle.

The end of the motor shaft is provided with a gear pinion 42 extending into the compartment 25 between the end wall 21 and transverse partition wall 26 for driving the mechanical transmission system which is housed in this compartment, and which serves to transmit movement from the drive pinion 42 to the driving gear 49 which extends beyond the lateral wall 22' of the lower shell 20. The gear 49 is in driving engagement with the driven gear 5 rigidly mounted on the axle 3 for the purpose of transmitting movement to the rear wheels 1 and 1. I The motion transmitting members of the mechanical transmission system T may comprise a sheet metal disc gear 45 mounted on a shaft 43 which is seated in journals 37 and 37 at the upper ends of posts or columns 35 affixed to the inner faces of lateral walls 22 and 22.

v The upper edge 33 of the rearmost portion of the lateral wall 22 is at a lower level than the upper edge of wall 22, but the post 35 adjacent to the latter is extended rearwardly at 35 to provide a journal seat 39 therein which is in horizontal alignment with the journal seat 39' at the upper edge 33 to provide bearings for a second shaft 44parallel to shaft 43, to which rotary movement is transmitted from the latter by the interengagement of pinion 46 which is integral with shaft 43 and sheet metal gear wheel 45, and which is in alignment with driven gear 47 on shaft 44, wherefrom extends gear portions 49 and 49 between which is formed a gap to free an intermediate. portion 48 of the shaft 44 for seating within the journal 39' in lateral wall 22.

ment.

A journal 39 for the second shaft 44, adjacent to the wall 22, is well below the upper edge of the lateral wall 22 and in order to secure the end of the shaft 44within its journal 43, a rib 58 is molded integrally with the inner face of the wall 52 of the upper shell 50 wherefrom projects downwardly a restraining pin 58', the free end of which abuts against the end of the shaft 44 at its journal bearing 39. The opposite end of the shaft 44 is maintained in its journal seat securely at portion 48 by the contact of the edge 52' of the rearrnost portion of the wall 52 of the upper shell 50 against the horizontal abutting edge 33 of the rearmost portion of wall 22' of the lower shell 20, to secure the shaft 44 in horizontal position to transmit its rotary movement to the driving pinion 49.

The housing for the control switch for the motor E is disposed forwardly thereof and may assume the form of a rotary disc 75 of insulating material, provided with suitable conductive segments, which is pivotally mounted to the underside of a square plate of insulating material 79 of hard or molded fiber sheeting which serves as a cover for the switching assembly. An opening 29 in the wall portion 23 of lateral wall 22' permits theprotrusion of the switch lever S from its housing to control the operation of the motor, by rotating the switch between its off position and its forward and backward positions. FIGS. 6 to 8 are circuit diagrams illustrating the alternative positions which may be assumed by the switch S to control the energization of the motor from its off position shown in FIG. 7 to the position shown in FIG. 6 for forward movement of the vehicle. As stated above, the

. switch is formed by a disc 75 of plastic of other insulating material to the upper surface of which is afi'lxed a short radial sector 76 of conductive material, such as brass or. copper which extends to the pivotal connection 83 between the disc 75 and plate 79. Another sector of the conductive material 77 subtends an arc greater than on the upper surface of disc 75. Three radiallydisplaced contact terminals R, R and R are disposed on the underside of cover plate 79 for selective contact with conductive segments 76 and 77 and wire connections are made thereto through openings in plate 79. A con ductor L extends from the L-shaped strap 82 at the rear end of chamber 56 for the battery, to the pivotal mounting 83 of the rotary switch 75 to connect the positive pole of the battery to the latter. The contact R adjacent to opening 29 is connected to the negative terminal of thebattery by way of conductor L; the second contact R is connected to one brush E of the motor E; while the third contact R is connected to the brush E of the motor E. Thus, when the switch lever S is in its neutral position, as shown in FIG. 7, there is no completion of the circuit between the motor and the battery by virtue of the superposition of contacts R and R" with the insulating portions of the disc '75. When the switch S is rocked in 'a clockwise direction, as shown in FIG. 6, the motor E is energized for actuation of the vehicle in a forward direction by the complefion of the circuit from the positive pole of the battery through conductor L, pivotal connection 83 and conductive sector 76, brush E through the motor, brush E", contact R", conductive segment 77, contact R and conductor L to the negative side of the battery. Upon rocking the switch lever S in a counterclockwise direction as shown in FIG. 8, the motor is energized by connecting the positive side of the battery to the brush E" of the motor, wherefrom the current passes through the motor and through the conductive segment 77 of the switch through line L to the negative side of the battery. This causes a reverse rotation of the motor and results in a backward movement of the vehicle.

The circuit connections to the motor are maintained securely by providing vertical ribs 58 at displaced points along the inner walls of the battery housing 56 to cushion the battery therein and to assure a secure contact between the positive pole thereof and strap 82 of springy conductive material at the rear end of chamber 56, while resilient conductive strap 81 makes contact with the external housing of the battery constituting the negative pole thereof. The straps 81 and 82 are formed of thin strips of metal which, together with the ribs 58, serve to seat the dry cell battery securely, without rattling. The straps 81 and 82 are fixed within the shell by the provision of lateral projections at their lower ends which are riveted to the bottom 57 of the shell.

Rectangular lugs 63 project from the wall 24 of the lower shell adjacent to the upper edge thereof for interengagement with sockets 65 which project below the bottom 57 of the upper shell, as shown clearly in FIG. 12. Upon the engage ment of these lugs and sockets, the component shells 20 and 50 may be sprung into interengaging position by the camming of retaining lug 62 into the recess 61 above the supporting lug 60 which serves to support the rear end of the module casing upon the rear edge 11 of the opening 15 in the base plate of the chassis. The initial interengagement of the module casing with the base-plate 10 of the chassis is indicated in FIG. 9, following which the module casing is rocked into its nested position within the vehicle body and is retained therein by the provision of spring tongue 70 affixed to the upper edge of the front wall 53 of the shell 50 and which is provided with a camming and supporting lug 73 at an intermediate point thereof which preferably is on the same level as lug 60, so that both the lug 60 at the rear end of the module casing and the lug 73 at the front end of the casing are supported by the baseplate of the chassis at a common level. The spring tongue 70 extends beyond lug 73 to provide a handle 72 to permit the convenient flexing of the tongue 70 to disengage the supporting lug 73 from the supporting edge 12 of the base-plate, when the disengagement of the module casing from the chassis is desired.

Thus, the module casing shown in FIGS. 1 and 2 is seated securely within the vehicle chassis by the lugs 60 and 73 resting on the base plate 10 at the rear end front edges 11 and 12, respectively. In addition, the module is cushioned in its positioning by the provision of projections 89 which press against the lateral projections 17 extending laterally from upwardly extending arms at the forward end thereof. Furthermore, the bracing pins 19 extending downwardly against the upper surface 55 of the upper shell at the rear portion thereof serve to impart a high degree of stability to the positioning of the module casing within the chassis body. Yet, an inward movement of flexible handle 72 effects an easy disengagement of the supporting lug 73 from edge 12 of the chassis so that the same may be rocked away therefrom into the position shown in FIG. 9, which permits the withdrawal of the supporting lug 60 from the edge 11, to effect the complete disengagement of the module from the chassis.

A different embodiment M of the module casing, which may be used interchangeably with the one described above in toy vehicles of all types, is illustrated in FIGS. 13 to 21. This embodiment imparts a capability to the toy vehicle to move in many different directions and the same is steered automatically in response to obstacles which may be encountered by the toy, as well as by the differences in tractive resistance offered by the surface on which it operates. This embodiment of the invention employs a small electric motor which is rotatable in a single direction only, and which comprises a switching device serving to control only the energization of the motor from its rest position.

The novel behavioral movements of the vehicle arises from the fact that the vehicle is advanced and steered in haphazard directions by a pair of actuating wheels which are disposed at the front of the vehicle, and which extend below the level of the front wheels of the latter, so that the actuating wheels may assume the steering function. In the second embodiment, the transmission system is disposed at the front of the vehicle with no interconnection with the gear wheel '5 mounted on the rear axle, so that the latter is idle when the second embodiment of the module casing is employed.

The module casing is of the same general outline in horizontal cross section in order that it may be inserted into the opening in the base-plate 10, for support thereby at the front and rear edges of the opening. However, instead of inserting the module casing with its rear end first, in order to engage driving pinnion 49 with the gear 5 on the rear axle as shown in FIG. 9, the second embodiment of the module casing is inserted as shown in FIG. 21, with the fixed lug 160 moved into initial engagement with front edge 12 and thereafter the rear end of the module casing M is snapped into position by flexing the tongue 170 inwardly in order to permit the supporting lug 173 to be cammed past the supporting edge 11 of the opening in the base-plate, which, upon outward flexing of the tongue 170, brings the supporting lug 173 into rest position on the baseplate.

The handle 172 on the flexible tongue 170 permits the removal of the module casing from the vehicle by flexing the supporting lug 173 forwardly which permits the withdrawal of the rear end of the module casing as indicated in FIG. 21, whereupon the supporting lug 160 may be withdrawn from the front end of the opening in the base-plate.

As shown in FIGS. 15 to 17, the module casing M may be formed of molded plastic material with the rearmost compartment 156 open at its top for the reception of the dry-cell battery B, an intermediate compartment forwardly of the rearrnost compartment for housing the small direct current motor P along a vertical axis which extends transversely to the longitudinal axis of the module, and a forward compartment which houses the transmission system for transmitting the movement from the pinion 101 connected to the upper end of the motor shaft through the series of interengaging pinions and gear wheels for ultimate actuation of the steering and traction wheels which are mounted in a rotatable housing H below the forward compartment 115. Transmission shaft 103 which is mounted vertically in the casing forwardly of the motor shaft 100, carries large gear 102 and pinion 104, which transmit the movement of pinion 101, affixed to the motor shaft, at reduced speed to gear wheel 105, which is mounted on the upper portion of vertical shaft 106, to rotate the annular sheet metal gear 107 at the bottom of shaft 106. The latter is in meshing engagement with the pinion 108 on the transversely disposed axle 112, on the opposite ends of which are mounted the steering and traction wheels 120. The latter extend below the base-plate 10 more than the vehicle wheels 2,2, which serves to lift the latter from the supporting surface (FIGS. 13 and 14), to incapacitate them.

A switch S, which is pivotally mounted on the wall between the rearmost and in termediate compartments 156 and 110, serves to control the circuit connections between the motor P in compartment 110 and the battery B in compartment 156, as indicated schematically in FIG. 20. As shown in FIG. 19, when the switch is in its On position the circuit to the motor P is completed from terminal P, conductor 133, contact 131, positive terminal 132 of the battery, through the battery and its housing which seats against the metallic strap 135, of L-shaped configuration, which is riveted at 136 to the rear of the compartment 156, and from which leads the conductor 134 to the other terminal P of the motor.

FIG. 18 shows the switch S in its Off position when the contact 131 is displaced from terminal 132 of the battery, so that the motor is in its deenergized state. When it is desired to operate the vehicle, the motor is merely switched to the position shown in FIG. 19, so that the motive power of the motor P is transmitted to the transmission system to the annular gear 107 which actuates the pinion 108 which causes the axle 112 to rotate and the housing H to move differentially to steer and advance the vehicle in both forward and rearward directions,

depending upon the obstacles encountered thereby. Thus,

when axle 112 and gear 108 are arrested by the wheels 120 striking an obstacle, the continued rotation of annular gear 107 causes housing H to rotate and thereby to free the wheels 120 from its obstacle, so that the vehicle may continue its travel in another direction.

.T he module casings M and M are readily interchangeable in all vehicle bodies, and the compartments for housing the batteries are of the same size to receive new replacements for the spent batteries.

lclaim:

l. A self-powered and untethered motor-driven wheeled toy vehicle composed of a vehicle body and chassis and comprismg a. a base-plate at the bottom of said chassis provided with an elongated opening disposed substantially along the longitudinal axis of said base-plate,

b. a pair of rotatable wheels mounted on said chassis adjacent to the front end of said base-plate,

c. a second pair of rotatable wheels mounted on said chassis adjacent to the rear end of said base-plate,

d. a pair of completely detachable self-contained and selfpowered interchangeable module casings adapted to be mounted on said chassis for engagement with said baseplate at the opposite ends of said opening between said pairs of wheels,

e. each module casing containing a single small rotary direct current electric motor having a rotary shaft, a dry-cell battery, and integrally mounted switching means for controlling the energization of said motor by said battery,-

. said switching means in one of said module casings adapted to energize said motor in opposite directions with a mechanical transmission system extending from said rotary shaft of the motor adapted to be detachably connected to at least one of said rotatable wheels to actuate said toy vehicle in opposite directions,

g. saidswitching means in the second one of said module casings adapted to energize the motor in a single direction,

h. a housing at the front end of said second module casing, rotatable on a vertical axis, and supporting traction wheels extending below said first-mentioned rotatable wheels at the front end of said base-plate, and

. a second mechanical transmission system in the second module casing extending from the rotary shaft of the motor therein to said traction wheels on said rotary housing for imparting differential movements thereto, to attain combined tractive and steering actuations.

2. A device as set forth in claim 1, wherein said elongated opening in said base-plate is of generally rectangular outline, and wherein each module casing is of corresponding outline in horizontal section adapted to fit within said opening, said casing having a lug projecting from one end thereof for engagement with the inner face of said base-plate and adapted for support thereby, and a flexible tongue extending downwardly from the upper portion of the opposite end of said casing and provided with an outwardly directed supporting lug adjacent to the free end thereof for permitting movement of said lastmentioned lug in an inward direction for passage into said opening preparatory to springing back in an outward direction for support by said base-plate at the opposite end of said opening from the point of support of said first-mentioned lug.

3. A device as set forth in claim 2, wherein the portions of said lugs adapted to rest on the opposite edges of said opening in said base-plate are in a common horizontal plane.

4. A device as set forth in claim 3, including stop members on said chassis above the opening in said base plate to confine each module casing securely within said chassis.

5. A device as set forth in claim 1, wherein said elongated opening in said base-plate is of generally rectangular outline, and said first-mentioned module casing is of corresponding outline in horizontal section adapted to fit within said opening,

said casing having a lug projecting from the rear end thereof for engagement with the inner face of said base-plate and adapted for support thereby at the rear edge of said opening, and a flexible tongue extending downwardly from the upper portion of the front end of said casing and provided with an outwardly directed supporting lug adjacent to the free end thereof for'permitting movement of said last-mentioned lug in an inward direction for passage into said opening preparatory to springing back in an outward direction for support by said base-plate at the front edge of said opening.

6. A device as set forth in claim 5, including a. a rotatable axle for the second pair of wheels,

b. a gear wheel fixedly mounted on said axle adjacent to one end thereof, and

c. said first-mentioned mechanical transmission system extending from said rotary shaft terminating in a driving gear extending laterally of said first module casing adjacent to the rear end thereof and in coupling engagement with said gear wheel.

7. A device as set forth in claim 6, wherein said first module casing is divided into a plurality of compartments with the mechanical transmission system being housed in the rearmost compartment, the motor being disposed in a compartment forwardly thereof, the battery in a front compartment, and the switching means in a compartment below the rear portion of said battery compartment and forwardly of said motor compartment.

8. A device as set forth in claim 7, wherein said first module casing with its plurality of compartments is constituted by a pair of interengaging molded plastic shells with externally disposed integral projections on one shell in coupled relation with externally disposed openings in the other shell.

9. A device as set forth in claim 8, wherein only said battery compartment is open to facilitate the insertion and removal of the battery.

10. A device as set forth in claim 9, wherein said motor is disposed with its rotary axis extending longitudinally of the axis of the module casing and said transmission system in the rearmost compartment comprises a pair of displaced shafts with transmission gears fixed thereon and journaled at the opposite lateral walls of one of said shells.

11. A device as set forth in claim 10, wherein the lateral walls of the other plastic shell confine the opposite ends of said shafts.

12. A device as set forth in claim 11, including vertical ribs molded integrally on the internal walls of said other plastic shell for securely retaining the opposite ends of said shafts in place.

13. A device as set forth in claim 12, wherein semi-circular seats are provided in the transverse walls at the opposite ends of said motor compartment for receiving the opposite ends of the motor housing, and a transverse projection extending from the inner wall of said other shell presses against the motor housing for confining the latter within its compartment.

14. A device as set forth in claim 7, wherein said switching means includes a central lever projecting laterally from said module casing and is provided with three positions to control the forward and reverse movements of the vehicle in addition to a neutral position whereat the motor is deenergized.

15. A device as set forth in claim 8, wherein said externally disposed projections on one shell comprise a pair of lugs extending forwardly of said compartment for said switching means, and a single centrally disposed lug extending rearwardly from the upper edge of the back wall of the rearmost compartment.

16. A device as set forth in claim 15, wherein the bottom of said other shell is provided with molded openings at the bottom of the battery compartment for receiving said pair of lugs and said supporting lug at the rear end of the module casing is provided with an opening for receiving said single lug of said one shell.

17. A device as set forth in claim 1, wherein said elongated opening in said base-plate is of generally rectangular outline,

and said second module casing is of corresponding outline in horizontal section adapted to fit within said opening, said casing having a lug projecting from the front end thereof for engagement with the inner face of said base-plate and adapted for support thereby at the front edge of said opening, and a flexible tongue extending downwardly from the upper portion of the rear end of said casing and provided with an outwardly directed supporting lug adjacent to the free end thereof for permitting movement of said last-mentioned lug in an inward direction for passage into said opening preparatory to springing back in an outward direction for support by said base-plate at the rear edge of said opening.

18. A device as set forth in claim 17, wherein said module casing is divided into a plurality of compartments with the rearmost compartment open at the top thereof for the reception of the dry-cell battery, the intermediate compartment forwardly thereof containing the motor disposed on a vertical axis, and the second transmission system extending between the motor and traction wheels disposed forwardly of said intermediate compartment.

19. A device as set forth in claim 18, wherein said second transmission system comprises a plurality of vertically disposed shafts with interengaging gear wheels affixed thereto and tenninating in said rotary housing at the lower end of the last vertical shaft at the forward end of said second module casing, an axle extending through said housing for mounting said actuating wheels at the opposite ends thereof, and a pinion on said axle in meshing engagement with an annular gear wheel on said last vertical shaft for imparting said differential movements to said axle and said housing for both propelling and steering said vehicle.

20. A device as set forth in claim 18, including a pivoted switch mounted between said rear and intermediate compartments and projecting below the bottom of said second module casing for controlling the connections between said battery and motor. 

1. A self-powered and untethered motor-driven wheeled toy vehicle composed of a vehicle body and chassis and comprising a. a base-plate at the bottom of said chassis provided with an elongated opening disposed substantially along the longitudinal axis of said base-plate, b. a pair of rotatable wheels mounted on said chassis adjacent to the front end of said Base-plate, c. a second pair of rotatable wheels mounted on said chassis adjacent to the rear end of said base-plate, d. a pair of completely detachable self-contained and selfpowered interchangeable module casings adapted to be mounted on said chassis for engagement with said base-plate at the opposite ends of said opening between said pairs of wheels, e. each module casing containing a single small rotary direct current electric motor having a rotary shaft, a dry-cell battery, and integrally mounted switching means for controlling the energization of said motor by said battery, f. said switching means in one of said module casings adapted to energize said motor in opposite directions with a mechanical transmission system extending from said rotary shaft of the motor adapted to be detachably connected to at least one of said rotatable wheels to actuate said toy vehicle in opposite directions, g. said switching means in the second one of said module casings adapted to energize the motor in a single direction, h. a housing at the front end of said second module casing, rotatable on a vertical axis, and supporting traction wheels extending below said first-mentioned rotatable wheels at the front end of said base-plate, and i. a second mechanical transmission system in the second module casing extending from the rotary shaft of the motor therein to said traction wheels on said rotary housing for imparting differential movements thereto, to attain combined tractive and steering actuations.
 2. A device as set forth in claim 1, wherein said elongated opening in said base-plate is of generally rectangular outline, and wherein each module casing is of corresponding outline in horizontal section adapted to fit within said opening, said casing having a lug projecting from one end thereof for engagement with the inner face of said base-plate and adapted for support thereby, and a flexible tongue extending downwardly from the upper portion of the opposite end of said casing and provided with an outwardly directed supporting lug adjacent to the free end thereof for permitting movement of said last-mentioned lug in an inward direction for passage into said opening preparatory to springing back in an outward direction for support by said base-plate at the opposite end of said opening from the point of support of said first-mentioned lug.
 3. A device as set forth in claim 2, wherein the portions of said lugs adapted to rest on the opposite edges of said opening in said base-plate are in a common horizontal plane.
 4. A device as set forth in claim 3, including stop members on said chassis above the opening in said base plate to confine each module casing securely within said chassis.
 5. A device as set forth in claim 1, wherein said elongated opening in said base-plate is of generally rectangular outline, and said first-mentioned module casing is of corresponding outline in horizontal section adapted to fit within said opening, said casing having a lug projecting from the rear end thereof for engagement with the inner face of said base-plate and adapted for support thereby at the rear edge of said opening, and a flexible tongue extending downwardly from the upper portion of the front end of said casing and provided with an outwardly directed supporting lug adjacent to the free end thereof for permitting movement of said last-mentioned lug in an inward direction for passage into said opening preparatory to springing back in an outward direction for support by said base-plate at the front edge of said opening.
 6. A device as set forth in claim 5, including a. a rotatable axle for the second pair of wheels, b. a gear wheel fixedly mounted on said axle adjacent to one end thereof, and c. said first-mentioned mechanical transmission system extending from said rotary shaft terminating in a driving gear extending laterally of said first module casing adjacent to the rear end thereof and in coupling engagement with said gear whEel.
 7. A device as set forth in claim 6, wherein said first module casing is divided into a plurality of compartments with the mechanical transmission system being housed in the rearmost compartment, the motor being disposed in a compartment forwardly thereof, the battery in a front compartment, and the switching means in a compartment below the rear portion of said battery compartment and forwardly of said motor compartment.
 8. A device as set forth in claim 7, wherein said first module casing with its plurality of compartments is constituted by a pair of interengaging molded plastic shells with externally disposed integral projections on one shell in coupled relation with externally disposed openings in the other shell.
 9. A device as set forth in claim 8, wherein only said battery compartment is open to facilitate the insertion and removal of the battery.
 10. A device as set forth in claim 9, wherein said motor is disposed with its rotary axis extending longitudinally of the axis of the module casing and said transmission system in the rearmost compartment comprises a pair of displaced shafts with transmission gears fixed thereon and journaled at the opposite lateral walls of one of said shells.
 11. A device as set forth in claim 10, wherein the lateral walls of the other plastic shell confine the opposite ends of said shafts.
 12. A device as set forth in claim 11, including vertical ribs molded integrally on the internal walls of said other plastic shell for securely retaining the opposite ends of said shafts in place.
 13. A device as set forth in claim 12, wherein semi-circular seats are provided in the transverse walls at the opposite ends of said motor compartment for receiving the opposite ends of the motor housing, and a transverse projection extending from the inner wall of said other shell presses against the motor housing for confining the latter within its compartment.
 14. A device as set forth in claim 7, wherein said switching means includes a central lever projecting laterally from said module casing and is provided with three positions to control the forward and reverse movements of the vehicle in addition to a neutral position whereat the motor is deenergized.
 15. A device as set forth in claim 8, wherein said externally disposed projections on one shell comprise a pair of lugs extending forwardly of said compartment for said switching means, and a single centrally disposed lug extending rearwardly from the upper edge of the back wall of the rearmost compartment.
 16. A device as set forth in claim 15, wherein the bottom of said other shell is provided with molded openings at the bottom of the battery compartment for receiving said pair of lugs and said supporting lug at the rear end of the module casing is provided with an opening for receiving said single lug of said one shell.
 17. A device as set forth in claim 1, wherein said elongated opening in said base-plate is of generally rectangular outline, and said second module casing is of corresponding outline in horizontal section adapted to fit within said opening, said casing having a lug projecting from the front end thereof for engagement with the inner face of said base-plate and adapted for support thereby at the front edge of said opening, and a flexible tongue extending downwardly from the upper portion of the rear end of said casing and provided with an outwardly directed supporting lug adjacent to the free end thereof for permitting movement of said last-mentioned lug in an inward direction for passage into said opening preparatory to springing back in an outward direction for support by said base-plate at the rear edge of said opening.
 18. A device as set forth in claim 17, wherein said module casing is divided into a plurality of compartments with the rearmost compartment open at the top thereof for the reception of the dry-cell battery, the intermediate compartment forwardly thereof containing the motor disposed on a vertical axis, and the second transmission system extending between the motor and traction wheels disposed forwardly of said intermediate compartment.
 19. A device as set forth in claim 18, wherein said second transmission system comprises a plurality of vertically disposed shafts with interengaging gear wheels affixed thereto and terminating in said rotary housing at the lower end of the last vertical shaft at the forward end of said second module casing, an axle extending through said housing for mounting said actuating wheels at the opposite ends thereof, and a pinion on said axle in meshing engagement with an annular gear wheel on said last vertical shaft for imparting said differential movements to said axle and said housing for both propelling and steering said vehicle.
 20. A device as set forth in claim 18, including a pivoted switch mounted between said rear and intermediate compartments and projecting below the bottom of said second module casing for controlling the connections between said battery and motor. 